Series Information

The World Economic Outlook (WEO) database contains projections of national accounts, inflation, unemployment rates, balance of payments, fiscal indicators, trade for countries and country groups (aggregates), and commodity prices for the world, major country groups (classified by region, stage of development, etc.), and many selected individual countries. The WEO is updated twice a year in April and September.

Data are available from 1980 to the present, and projections are given for the next two years. Exact availability will vary greatly from country to country.

AssumptionsA number of assumptions have been adopted by the IMF for the projections presented in the World Economic Outlook. It has been assumed that real effective exchange rates will remain constant at their average levels during July 5–August 2, 2006, except for the currencies participating in the European exchange rate mechanism II (ERM II), which are assumed to remain constant in nominal terms relative to the euro; that established policies of national authorities will be maintained; that the average price of oil will be $69.20 a barrel in 2006 and $75.50 a barrel in 2007, and remain unchanged in real terms over the medium term; that the six-month London interbank offered rate (LIBOR) on U.S. dollar deposits will average 5.4% in 2006 and 5.5% in 2007; that the three-month euro deposits rate will average 3.1% in 2006 and 3.7% in 2007; and that the six-month Japanese yen deposit rate will yield an average of 0.5% in 2006 and of 1.1% in 2007. These are, of course, working hypotheses rather than forecasts, and the uncertainties surrounding them add to the margin of error that would in any event be involved in the projections. The estimates and projections are based on statistical information available through end-August 2006.

Data ConventionsIn line with recent improvements in standards of reporting economic statistics, several countries have phased out their traditional fixed-base-year method of calculating real macroeconomic variables levels and growth by switching to a chain-weighted method of computing aggregate growth. Recent dramatic changes in the structure of these economies have obliged these countries to revise the way in which they measure real GDP levels and growth. Switching to the chain-weighted method of computing aggregate growth, which uses current price information, allows countries to measure GDP growth more accurately by eliminating upward biases in new data. Currently, real macroeconomic data for Albania, Australia, Austria, Azerbaijan, Canada, Czech Republic, Denmark, euro area, Finland, Georgia, Germany, Greece, Iceland, Ireland, Italy, Japan, Kazakhstan, Lithuania, Luxembourg, the Netherlands, New Zealand, Norway, Portugal, Russia, Slovenia, Spain, Sweden, Switzerland, the United Kingdom, and the United States are based on chain-weighted methodology. However, data before 1996 (Albania), 1988 (Austria), 1995 (Czech Republic), 1990 (Denmark), 1995 (euro area), 1991 (Germany), 1995 (Greece), 1990 (Iceland), 1994 (Japan), 1995 (Luxembourg), 1987 (New Zealand), 1995 (Russia), 1995 (Slovenia), and 1995 (Spain) are based on unrevised national accounts and subject to revision in the future.

The following conventions have been used throughout the WEO:* Domestic economy series are expressed in billions of national currency units. * External accounts series are expressed in billions of U.S. dollars. * Billion means a thousand million.

These and other FAQs are available on the IMF website at: http://www.imf.org/

1) WEO Database

Q. How often is the WEO database updated?A. The WEO database is updated twice a year, in April and September. Advanced economies and the largest developing countries, which account for 90% of world output, provide projections for each WEO exercise. Smaller countries provide projections at the time of the IMF's regular Article IV consultations with member countries unless world developments necessitate more frequent updates.

Q. What changes have been made to the WEO database in this issue (September 2006) compared to the previous edition?A. For the September 2006 publication, data for Liberia are included. Also, following the declaration of independence from Serbia by Montenegro, it has been determined that Serbia is the continuing state of the former state union of "Serbia and Montenegro" and that Montenegro has seceded as a new independent state. In addition, data notes at the country, series and subject levels, and population data are now made available for the WEO database.

Q. What explains differences between WEO and International Financial Statistics (IFS) data?A. The data appearing in the WEO are provided to the research department at the time of the WEO exercise, not on a continual basis. The historical data and projections are based on the information gathered by the IMF country desk officers in the context of their missions to the countries and ongoing analysis of the evolving situation in member countries; projections are staff estimates. The data published in the Statistics Department's International Financial Statistics are gathered as part of an ongoing data collection effort in which member country statistical agencies provide public statistics to the IMF. Because of differences in data collection techniques, methodological issues, focus, and timing, the data in the International Financial Statistics and the WEO may differ.

Q. How do I know if data are actual, preliminary, or projected?A. In the series description, the beginning of the estimated data is included within brackets. This information is not available for WEO country groups' data.

Q. Do you have higher frequency data such as quarterly or monthly data?A. The IMF does not publish monthly or quarterly data in the WEO database. Other IMF databases and other Moody's Analytics products offer additional data. For more information, please contact us via help@Moody's Analytics or contact your marketing representative.

Q. Do you have data prior to 1980?A. No. The IMF stopped providing data prior to 1980 due to difficulties in verifying the accuracy of the historical data in its WEO database. However, you may find more historical coverage in the sister publication from the IMF: the International Financial Statistics, also available via Moody's Analytics. For more information, please contact us via help@Moody's Analytics or contact your marketing representative.

Q. Do you have long- and/or medium-term forecasts?A. No. The IMF does not provide medium-term and long-term projections in its WEO database. Other Moody's Analytics products do provide longer forecast horizons. For more information, please contact us via help@Moody's Analytics or contact your marketing representative.

Q. Are there any other data available besides what is downloadable from the WEO database?A. No. All of the data that can be released to the public are already incorporated into the WEO database. For more IMF data, or data from other sources, please contact us via help@Moody's Analytics or contact your marketing representative.

Q. What is the constant price base year for GDP? Is it constant across all countries?A. The information on base years for national accounts at constant prices is gathered from IMF country desk officers and are country-specific. This information is provided in the Country Information summary page.

Q. Is there a real global GDP dollar series that can be used to compare economy size across countries? A. The IMF does not report the value of constant price GDP in a common currency (say U.S. dollars) for the world. However, The IMF publishs a world GDP indexed in 2000, which does measure changes in the world output. The index is constructed as a weighted average of real growth rates for all reporting countries. A country's weight for this average is its share of nominal GDP at purchasing-power-parity (PPP) exchange rates.

Q. How often are GDP estimates revised? A. The number of revisions to each country's GDP data is country-specific. The IMF collects historical data and projections from each IMF country desk officer, and, in turn, the national authorities provide the country desk officer with their most current updates. Although there may be several iterations, each publication takes into account the most recent revisions available, prior to publication.

Q. For the countries that adopted the euro, how did you convert the series expressed in national currency?A. The WEO used the fixed conversion rates between the euro and the currencies of the member states adopting the euro to transform the data prior to 1999. The following are the irrevocable euro conversion rates as adopted by the Council of the European Union on January 1, 1999:

Q. What is the difference between general government gross and net debt?A. General government gross debt comprises the stock (at year end) of all government liabilities (both to residents and nonresidents). On the other hand, net debt refers to government liabilities minus government assets (domestic as well as foreign). To avoid double counting, the data are based on a consolidated account (eliminating liabilities and assets between components of the government, such as budgetary units and social security funds). General government refers to the central government plus state, provincial, or local governments. Fiscal data reflect national accounts definitions.

Q. Does the WEO publish exchange rate data?A. The WEO does not provide exchange rates. The IMF's IFS provides this data as well. This database is also available from Moody's Analytics. For more information, please contact us via help@Moody's Analytics or contact your marketing representative.

Q. Is there a list of WEO countries that are chain-weighted?A. You may find the list of chain-weighted countries in the Assumptions and Data Conventions listed above. At this time, this only applies to the Gross Domestic Product, constant prices series.

Q. Is there a reference page available listing which countries are included in the aggregates—for example, advanced economies, ASEAN-4, etc.?A. The list of Country Groups can be found in the Groups and Aggregates link.

Q. How does the WEO categorize advanced versus other emerging markets and developing countries?A. The main criteria used by the WEO to classify the world into advanced and emerging markets are (1) per capita income level, (2) export diversification, and (3) financial market integration. Note, however, that these are not the only factors considered in deciding the classification of countries. As it says in the WEO Statistical Appendix, "Rather than being based on strict criteria, economic or otherwise, this classification has evolved over time with the objective of facilitating analysis by providing a reasonably meaningful organization of data."

Q. What is a PPP exchange rate?A. The PPP between two countries is the rate at which the currency of one country needs to be converted into that of a second country to ensure that a given amount of the first country's currency will purchase the same volume of goods and services in the second country as it does in the first. In the WEO online database, it is expressed as local currency per U.S. dollar.

The International Comparisons Program (ICP) is a global statistical initiative that produces internationally comparable PPP estimates. The PPP exchange rate estimates, maintained and published by the World Bank, the OECD, and other international organizations, are used by WEO to calculate its own PPP weight time series. For more information, you can go to the World Bank website. Under the section "Statistics and Data" there is a link to ICP that is about PPP surveys and methodologies.

Q. What is Gross domestic product based on PPP valuation of country GDP?A. It is calculated by dividing a country's nominal GDP in its own currency by the PPP exchange rate. This measure of a country's GDP is used in the WEO online database to construct aggregate indicators (weighted averages) of changes for example in consumer prices, nominal and real GDP growth, and nominal and real GDP per capita growth for groups of countries when the indicator being measured is expressed in local currency.

Q. How is GDP at PPP exchange rates used to calculate WEO country group data? Will I be able to calculate aggregated data based on a different country grouping using PPP exchange rates?A. Country group data or aggregates relating to the domestic economy, whether growth rates or ratios, are weighted by GDP valued at PPPs as a share of world total or country group GDP. Annual inflation rates are simple percent changes from previous years ((CPIt/CPIt-1)-1), except for other emerging market and developing countries where the rates are based on logarithmic differences (log(CPIt)-log(CPIt-1)). This exception to the methodology only applies for the inflation series and only whenever a group is comprised of countries belonging to the other emerging market and developing countries group. Therefore, for the advanced economies, the conventional methodology for aggregating is used.

For example, the consumer price index for all advanced economies is calculated by multiplying each country's CPI inflation times its share (PPP weight) of the group's total gross domestic product based on PPP valuation of country GDP. A country's share (or weight) is its nominal GDP at PPP exchange rates divided by the sum of nominal GDP at PPP exchange rates for all countries in the group. Summing the product of each country's inflation rate and PPP-GDP weight produces a weighted average growth rate of consumer prices for one year. After the weighted average growth rates for all years have been calculated, they are transformed into an index. You can follow this example to create your own aggregated data based on your own country groups. For further detail on the PPP-based weights, follow this link: http://www.imf.org/external/pubs/ft/wefs/1993/eng/studies/pdf/93WEOss3.pdf.

Q. What other methodologies are used to calculate WEO country group (aggregated) data? 1) Aggregates for unemployment rate are weighted by labor force as a share of group labor force.2) Aggregates relating to the external economy are sums of individual country data after conversion to U.S. dollars at the average market exchange rates for balance of payments data and at end-of-year market exchange rates for debt denominated in non-U.S. dollars.3) Aggregates of changes in foreign trade volumes and prices, however, are arithmetic averages of percentage changes for individual countries weighted by the U.S. dollar value of exports or imports as a share of total world or country group exports or imports.

Q. Why are United States data different if expressed in U.S. dollars or PPP exchange rates when the implied conversion rate is equal to 1?A. The PPP-valued GDP series is updated once at the beginning of the year while the GDP series is updated throughout the year as new information arrives. The main purpose for PPP-valued GDP is to calculate WEO group aggregations and for this reason, the data are kept constant throughout the year. Thus, the formula applies only once at the beginning of the year.